JP 2008-199828A published by the Japanese patent office in the year 2008 discloses a charge control circuit that executes charge control under which a secondary battery module, constituted with a plurality of unit cells layered one on top of another, is charged. The charge control circuit detects voltages at the unit cells, compares the voltage at the secondary battery module with a predetermined voltage value based upon the voltages at the unit cells and controls the current output from a battery charger based upon the comparison results.